Matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI/FTMS), operating in the negative ion mode, is used to directly observe sugar alcohol borate complexes in a number of plant fractions. The method involves virtually no sample workup and, in the case of celery phloem sap, requires only 40 nL of sap to observe the borate complex. The isolation and characterizati...

The Tris-HCl and phosphate-borate forms of glutaminase (EC 3.5.1.2, L-glutamine amidohydrolase) are both activated and protected from inactivation by phosphate and carboxylic acids. The Tris-HCI enzyme is less sensitive to this activation, but more sensitive to glutamate inhibition than the phosphate-borate enzyme. Plots of activity against concentration of activating anions are generally sigmo...

Evidence for an “RNA world,” an episode of life on Earth during which RNA was the only genetically encoded component of biological catalysts, is found in the ribosome (1), catalytic RNA molecules (2), and contemporary metabolism (3). That RNA could form spontaneously and persist under prebiotic conditions has been doubted, however (4, 5). Ribose and its sister pentoses (arabinose, xylose, and l...

A major problem encountered in the large-scale purification of the bivalent anti-T cell immunotoxin, A-dmDT390-bisFv(G4S), from Pichia pastoris supernatants was the presence of host glycoproteins exhibiting similar charge, size, and hydrophobicity characteristics. We overcame this problem by employing borate anion exchange chromatography. The borate anion has an affinity for carbohydrates and i...

We present an infrared spectroscopy and X-ray diffraction study of hafnium oxide gate dielectric films deposited from hafnium tetra–tertbutoxide, Hf(OC(CH3)3)4. We characterize the crystal phase as a function of thickness and detect the chemical state of impurities in this high-permittivity (high) material. The HfO2 films are composed of monoclinic crystallites in an amorphous matrix. The cryst...

Two new zinc phosphonates, [(C5H14N2)0.5Zn5(HO3PCH(OH)CO2)(O3PCH(OH)CO2)3 x 2 H2O] x 2 H2O (1) and [(C4H12N2)Zn2(O3PCH(OH)CO2)2] (2), have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction along with powder XRD, elemental analysis (EA), IR, and thermogravimetric analysis (TGA). In compound 1, [ZnO6] octahedra and [ZnO5] square-pyramids are brid...

In the title compound, [Fe(C10H15N2O2)Cl2]·2H2O, the Fe(III) ion is coordinated by two N and two O atoms of the tetra-dentate 2-{(2-hy-droxy-eth-yl)(pyridin-2-ylmeth-yl)amino}-ethano-late ligand and by two chloride anions, resulting in a distorted octa-hedral coordination sphere. The average Fe-X (X = ligand N and O atoms) and Fe-Cl bond lengths are 2.10 and 2.32 Å, respectively. In the crystal...

Certain bioflavonoids inhibit the glycolysis of variety of tumor cells by interfering with the generation of adenosine diphosphate and inorganic phosphate which are required for glycolysis. Tetra- and pentahydroxy flavones with hydroxyl groups as 3, 3', 4', 5, and 7 (e.g., quercetin) are the most active. They inhibit the activity of isolated Na+-K+-adenosinetriphosphatase of the plasma membrane...

The 3-glucosides of nonamidated lithocholic, chenodeoxycholic, ursodeoxycholic, deoxycholic, and cholic acids, and their double conjugate forms with glycine and taurine were synthesized. The key reactions used were 1) beta-D- glucosidation at C-3 by the Koenigs-Knorr condensation reaction of 3 alpha-hydroxylated bile acid methyl (or p-nitrophenyl) esters with 1 alpha-bromo-1-deoxy-2, 3, 4, 6-te...